Roland is a police officer in pursuit of a fleeing rape suspect. The chase is on foot, and Roland is a much faster runner than his partner. He catches the suspect out of sight of his partner. When his partner, Ted, arrives on the scene, he observes Roland striking the suspect, despite the fact that the suspect is already in handcuffs.
The suspect does file a complaint with Internal Affairs, and Ted is questioned about the incident. Ted tells the investigator that he observed nothing out of the ordinary: when he arrived at the scene the suspect was in custody and Roland was reading him his rights. This is an example of:
The Blue Curtain of Secrecy.